Monday, March 6, 2006

Re: On learning from accidents: I collect slide rules as a hobby. One common topic in discussions with other collectors: Modern calculators and computers make it too easy to fall into the false-precision trap (e.g. 10-digit answers to problems with 3-digit input data). It's harder to do this with a slide rule, partly because of the limited precision of the instrument, but also because the scales graphically illustrate the decreasing significance of the rightmost digits. Successively finer scale divisions are squeezed closer together, but all digits on a calculator display are equally prominent. (Via RISKS Digest.) With current processor speeds and memory sizes, it might be practical to propagate error information in safety-critical calculations, using interval arithmetic for instance. 10:51:21 PM

telecom pop quiz: For three points who said Together, we will lead the way into a new era of converged and bundled communications, video and entertainment services while also improving our ability to manage complex networks. C. Michael Armstrong, 1999 (AT&T + TCI + MediaOne -> AT&T) Edward Whitacre, 2006 (SBC + AT&T + BellSouth -> AT&T) I leave it up to the reader to search out the answer. (Via tingilinde.) I'd suggest searching for insanity+einstein instead. 8:55:56 PM